De-arming device



Oct. 22, 1963 J. VANOVER 3,107,618

DE-ARMING DEVICE Filed Oct. 27, 1961 Z'SheetS-Sheet 1 m 4 l M MW a w w mm I I W \i l 5 li a 1 5 s 1 E M FlG. 2A.

ATTORNEY.

FlG.

3 ,l had i 8 Patented @ct. 22., l 963 ice 3,107,618 nn-Antvmso nnvrcn 7 Claims. (Cl. 102-79) (Granted under Titie 35, US. Code (1952), see. 2%)

The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to de-arming means for warhead fuzes; and more particularly to means for dearming warhead fuzes in missiles of the type which make use of acceleration forces to arm the fuze, for example, the type of missile shown and described in US. Patent No. 2,948,219, issued August 9, 1960, to Winfred F. Sapp for Rocket Fuze.

Missiles fired from ground-to-air and air-to-air may be equipped with different types of fuzes; the fuze may be of the impact detonating type or a proxim ty fuze or any other type which senses the target to detonate the warhead of the missile. However, with such missiles, where the air target is completely missed, the missile continues to the ground and detonates there. Where such detonation occurs over enemy territory there is no objection; however, where detonation occurs in areas occupied by friendly troops there is a danger to personnel and equipment. It has been proposed to equip such missiles with an additional firing means to detonate the missile in midair in the event that the air target is completely missed. Such provision has the disadvantage that when detonation in mid-air occurs over friendly troops they are subjected to a rain of missile fragments which endanger them.

It is therefore an object of this invention to provide a de-arming means in missiles of the type described which in the event that the missile misses its air target it is then sterilized or de-armed and falls to the ground as a dud.

Another object of the invention is to provide a delay and actuating means which sterilizes or de-arrns the fuze of the missile a predetermined period of time after arming of the missile, which interval of time is greater than the time necessary to intercept the target but of less time than that needed to impact on the ground.

Still another object of the invention is to provide a pyrotechnic means which is initiated with arming of the missile and provides a time delay and actuating means for sterilizing or de-arming the missile before impact on the ground should the missile miss its air target.

A still further object of the invention is to provide an improved pyrotechnic delay and actuating means which is safe to handle and yet which operates in a reliable manner to sterilize or de-arm the missile.

A feature of the invention is the provision of an improved pyrothechnic delay means which initiates gasgenerating material, the gas being used to actuate means for de-arming the fuze of the missile.

A further feature of the invention is the provision of a movable element in the firing train of the missile, which element is moved out of the firing train for interrupting the firing train and thereby sterilizing or de-arming the missile. This provides a very simple arrangement whereby the missile is live to detonate on its air target but is rendered a dud before coming to the ground.

A still further feature of the invention is the provision of a gas operated piston powered by gas from gas-generating material, the piston having connected thereto actuating means which withdraw retaining means from the movable element, thus permitting movement of the element from the firing train and the sterilization or de-arming of the missile.

Other objects, features and many of the attendant advantages of this invention will become readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is an elevational view, partly in section, of a warhead fuze to which de-arming means in accordance with the invention have been adapted;

FIG. 2 is a fragmentary side elevation, generally along line 2-2 of FIG. 1, of the arming rotor and associated parts with portions thereof being cut away, the arming rotor being in the unarmed position thereof;

FIG. 2A is a view similar to FIG. 2, but showing the arming rotor in the armed position thereof;

FIG. 3 is a horizontal sectional view, generally along line 3-3 of FIG. 1, looking in the direction of the arrows;

FIG. 4 is a horizontal sectional view, generally along line 44 of FIG. 1, looking in the direction of the tarrows;

FIG. 5 is a vertical sectional view, generally along lines 55 of FIGS. 3 and 4, looking in the direction of the arrows and showing a movable element of the firing train retained in alignment with the remainder of the firing train;

FIG. 5A is a view similar to FIG. 5, but showing the retaining means withdrawn and the movable element moved out of alignment with the remainder of the firing train;

FIG. 6 is a fragmentary sectional view, generally along line 66 of FIG. 4, showing the camming means for withdrawing the movable element retaining means; and

FIG. 7 is a fragmentary sectional view, generally along line 7-7 of FIG. 4, showing the spring-loaded element for initiating the pyrotechnic delay means and the pin for holding the element in inactive position.

Referring now to the drawings, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown, in FIG. 1 a portion of a missile or projectile 10 which is provided with a warhead fuze 11. Fuze 11 is of the type shown and described in the aforementioned US. Patent No. 2,948,219 and only pertinent portions thereof will be herein referred to for an understanding of the relationship of the sterilizing or de-arming means of this invention to the fuze of the patent; for a detailed description of the fuze reference may be had to the aforesaid patent.

As will be seen from FIG. 1, fuze 11 is provided with the usual nose ogive 12 which houses arming roto 13, the rotation of which, under acceleration forces, is controlled by set back weight 14. Rotor 13 is provided with a diametrical bore 15 within which is carried a pyrotechnic train 16 which is aligned, after rotation of rotor 13 under acceleration forces, with firing pin 17 and lead-in opening 18.

Adjacent lead-in opening 18 there is provided a first tetryl pellet or similar type element 19 which is movably supported for reasons hereinafter appearing. In close proximity to tetryl pellet 19 is a second tetryl pellet 21, next to which is lead-in 22 of a booster charge 23.

With the elements of the firing train aligned as shown and described, movement of firing pin 17 under impact drives it into the pyrotechnic train 16 which initiates tetryl pellet 19 and sets off tetryl pellet 21 and booster charge 23 to detonate the warhead main charge (not shown).

Tetryl pellet 19 is contained within an upper chamber 24 forming part of a housing 25, tetryl pellet 21 being contained in the lower half of housing 25 which is formed with a chamber 26.

Turning now to FIGS. 3 and 5, tetryl pellet 19 is shown supported in a slidable member 27 which is confined to a line of movement by a pair of slide guide elements 28 supported in chamber 24 in any suitable manner. Slidable member 27 is formed with a bore 29 which contains an expansion spring 31, one end of the'spring reacting against the bottom of the b e and the other end of the spring reacting against the side of housing The reaction of the expansion spring 31 biases slidable member 217 in -a direction to move tetryl pellet from the position shown in FIGS. 3 and 5, in which the tetryl pellet is in alignment with tetryl pellet 21 and the remainder of the firing train, to the position shown in Flu. 5A in which the tetryl pellet 19 is out of alignment with the remainder of the firing train.

Tetryl pellet 19 is maintained in alignment with the remainder of the firing train by means of a detent pin 32 which engages slidable member 27 and holds it in the position shown in FIGS. 3 and 5. Associated with the detent pin 32 is a spring 33 which urges the pin toward retaining position. With the tetryl pellet l9'disposed in the position shown in FIG. 5A, that is, out of alignment with the remainder of the firing train, the flame from the pyrotechnic train 16- will impinge upon the metallic slidable member 27, rather than upon the tetryl pellet l9, and will not initiate the pellet. Thus, movement of tetryl pellet 19 out of alignment with the remainder of the firing train serves to sterilize or de-arm the missile fuse.

The means for withdrawing the detent pin 32 and permitting movement of slidable member 27 to move tetryl pellet 19 out of alignment with the remainder of the firing train will now be described. Detent pin 32 is provided with a collar 34 aifixed thereto and disposed in chamber of housing 25. Associated with the detent pin 32 is a pyrotechnic delay and actuating means 35', which includes a forked wedging member 36 having curved surfaces 37 engaging collar 34 for camming the detent pin 32 out of retaining position upon movement of member 36, the edges of the collar being rounded to facilitate the camrning. Forked member 36 is attached to connecting rod 33 of a piston 39 operating in a piston cylinder 41. Sealing means 42 are provided for gas tight engagement of piston 39 with the piston cylinder. Cylinder 41 is part of a casing 43 which is suitably secured in chamber 26 i and contains a gas generating element 44, a pyrotechnic delay element 45, and a primer 46 which initiates element 45 which, in turn, ignites element 44. Element 45 is selected to provide any desired interval of delay, for example, 10 seconds, at the end of which element 44 is ignited. Element 44 may be a black powder pellet or the like. Primer 46 is of the stab type in which the primer material, for example, lead azide, is contained in a metallic casing and is adapted to be set off as a result of piercing by a firing pin 47. Burning of element 44 generates gas which expands in the casing 43 and operates piston 39 to withdraw pin 32 and release member 27.

Firing pin. 47 is disposed within chamber 26 and is mounted for swinging movement on a screw pivot bolt 48 which is provided with a collar 49 against which firing pin 47 bears. Associated with firing pin 47 is a torsion spring 50 which urges the firing pin toward primer piercing position. Also associated with firing pin 47 is a detent or lock pin 51 of considerable length, the lower end 52 of which is norm-ally disposed in the path of the spring loaded firing pin 47 and serves to retain the firing pin 47 out of primer piercing position. The detent or lock pin 51 has a collar 53 against which an expansion spring 54 reacts to bias the lock pin from firing pin retaining position. Pin 51 extends upwardly through suitable openings, the upper end 55 thereof being in abutting engagement with a hub 56 which forms part of rotor 13, FIGS. 1 and 2. Hub 56 is provided with a bore 57 which is adapted to 'receive the upper end 55 of pin 51 when the arming rotor 13 has rotated into armed position, FIG. 2A. The extent of travel of the upper end 55 of pin 51 into bore 57 is sufiicient to withdraw the lower end 52 of pin 51 from firing pin 47, FIG. 7, which releases the firing pin for piercing of the primer 46 and the initiation of the pyrotechnic delay and actuating means 35..

From the foregoing description, the operation of the sterilizing or d e-arming means of this invention should be apparent. However, briefly and in summary, after firing of the missile the acceleration forces encountered operate to rotate the arming rotor 13 into aumed position thereof, FIG. 2A. With arming rotor 13 in the armed position, the upper end 55 of pin 51 enters bore 57 and the lower end 52 of pin 51 is withdrawn from firing pin 47, thus releasing the firing pin for piercing of primer 46 and initiation of the pyrotechnic delay and actuating means 35 which provides a predetermined delay prior to sterilization or de-arming of the fuze 0f the missile. In the event that the missile has not impacted on an air target, at the end of the delay period the burning out of the pyrotechnic delay element 45 ignites the black powder pellet 44, the burning of which generates gas which expands in casing 43 and forces piston 39 and attached member 35 toward detent pin 32 for withdrawing the sme and releasing slidable member 27, thereby permitting movement of member 27 and tetryl pellet 19 for placing pellet 19 out of alignment with the rest of the firing train and thus sterilizing or tie-arming the fuze of the missile.

While the sterilizing or de-arming means of this invention has been described in association with a fuze of the impact type, it is obvious that it could be used with fuzes of other types and that obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be under stood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In combination, a missile comprising a charge, a firing train for detonating said charge, said firing train including a movable element normally in fixed operative relation with the remainder of the firing train for rendering the same effective to detonate said charge, and pyrotechnic delay and actuating means for moving said element out of said operative relation with the remainder of said firing train and die-arming the missile.

2. In combination, a missile of the type having a firing train armed by acceleration forces, said firing train cornprising a movable element normally in fixed operative relation with the remainder of said firing train, and means including a pyrotechnic delay element for moving said movable element out of said operative relation to said firing train; whereby said firing train is interrupted and the missile is dc-armed.

3. In combination, a missile having a firing train comprising a plurality of elements normally in alignment, one of said elements being movable out of alignment, and delay and actuating means connected to said last-named element for moving the same out of alignment with the other elements for interrupting said firing train and dearming said missile, said delay and actuating means comprising gas-operated piston means.

4. In a missile of the type having a firing train, said firing train comprising an arming rotor carrying a portion fsaid train, said arming rotor being rotatable in response to acceleration forces to align said portion of said firing train with the remainder thereof and arm said missile, said firing train further comprising a movable element normally in fixed alignment with the remainder of said.

firing train, means biasing said element out of alignment with the remainder of said firing train, retaining means holding said element in'alignrnent in said firing train, pyrotechnic delay and actuating means, means connected to said retaining means, and means released uponrotation of said arming rotor for initiating said pyrotechnic delay and actuating means, said pyrotechnic delay and actuating means, means comprising means for withdrawing said retaining means from said movable element; whereby said biasing means moves said movable element out of alignment with the remainder of said firing train and said missile is dc-armed.

5. In a missile having a firing train, means for dear-ming the missile, said means comprising a movable firing train element held in alignment with the remainder of the filing train by retaining means, means biasing said element out of said alignment, and actuating means connected to said retaining means for withdrawing the same from said element, said actuating means comprising pyrotechnic delay means.

6. In combination, a missile, means for arming said missile, said means comprising actuable means for aligning the elements of a firing train, and means for de-arming said missile, said de-arming means comprising means for moving one of the elements of said firing train out of alignment with the remainder of the firing train and means released by said actuable means for initiating said de-arming means.

7. The combination of claim 6, wherein said one firing train element is mounted for movement and normally biased out of alignment With the remainder of the firing train, retaining means holding said one firing train element in alignment with the remainder of the firing train, and delay and actuating means for Withdrawing said retaining means from said one firing train element.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN COMBINATION, A MISSILE COMPRISING A CHARGE, A FIRING TRAIN FOR DETONATING SAID CHARGE, SAID FIRING TRAIN INCLUDING A MOVABLE ELEMENT NORMALLY IN FIXED OPERATIVE RELATION WITH THE REMAINDER OF THE FIRING TRAIN FOR RENDERING THE SAME EFFECTIVE TO DETONATE SAID CHARGE, AND PYROTECHNIC DELAY AND ACTUATING MEANS FOR MOVING SAID ELEMENT OUT OF SAID OPERATIVE RELATION WITH THE REMAINDER OF SAID FIRING TRAIN AND DE-ARMING THE MISSILE. 